Rotary drier



Patented Feb. 21, 1922.

3mm Alfredj hlfzy A. MACKAY.

ROTARY DRIER.

APPLICATION FILED JUNE 3, 1920.

' UNITE o;- STATE-S "ALFRED liIIAU'KAY, or-rnrnannnrnra, rnnnsrrvanra,assronon 'ro or riroonnsrown, new annsnr.

PATENT OFFICE.

GEQRGE B.

ROTARY DRIER.

, Application fi1ei1..1une 3,

T0 aZZ whom it mag concern i Be it known thatI, .AIirRED MAGKAY', acitizen of the United States, res ding at Philadelphia, in the countyofPhila'delphia and State of Pennsylvania, have invented new and usefulImprovements in Rotary Driers, of whiclrthe following is aspecification.

My invention relates to rotary driers, such as are used in the papermaking art, and consists in certain improvements I have made in theconstruction of the cylinders over which the web to be dried passes.These cylinders are heated internally by steam, which necessarilycondenses as it gives off its heat. The high speeds at which thesecylinders are run in modern practice makes it difficult to remove thewater of condensation of the steam, as it is naturally thrown and heldout by centrifugal force on the inner periphery of the cylinder. Specialmeans has therefore to be provided to direct the water of condensationaway from the periphery and out of the cylinder.

Means for this purpose have heretofore been devised, and my inventionconstitutes an improvement upon such prior means. It has been proposedto mount a spirally arranged open gutter or conductor on the innerperiphery of the cylinder, whereby the water is directed to a reservoiror pocket in one end of the cylinder, from which it is dischargedthrougha pipe running through the cylinder trunnion. Such a constructionforms the subject matter of U. S. Patent No. 666,477, issued Jan. 22,1901, to A. A. Hunting. An improvement upon his means is the subjectmatter of U. S. Patent No. 1,258,055, issued to C. L. St. Clair and J.H. Hoffman on March 5, 1918, in which a plurality of spiral or helicalribs, are secured to the inner periphery of the cylinder and lead intothe outermost convolution of a flat spiral chamber constituting one endof the cylinder.

It has been found, in the use of drying cylinders constructed accordingto this last mentioned patent, that the water of condensation is notremoved completely as fast as it is formed, which difliculty I ascribeto the fact that there are several spaced inlets for the water to enterthe spiral chamber and that, therefore, interference between the severalstreams of water takes Specification of Letters Patent.

Patented Feb; 2 1, 1922. 1920. Serial 11o. 386,212.

place, which interferes with its smooth and regular outflow.

To remedy this defect, I have devised the construction and arrangement,hereinafter described in connection-with the accompanying drawing, inwhich Fig. 1 is a longitudinal section of one end of a drier cylinderequipped with the water removing means of my invention, and

Fig. 2 is a cross section of the same on the line 2-2 of Fig. 1.

10 is the drier cylinder, provided with the usual journal head 11 andjournal or trunnion 12. 13 is the outlet or drain pipe for the condensedsteam, leading from the central chamber or pocket 14: and passing outthrough the other end of the. cylinder. Three volute spiral chambers,15, 16 and 17, convey the water into said pocket, and the helicaldeflector ribs 18 guide the water into said spiral chambers, the latterbeing each provided with an inlet 19 at the point where the ribterminates.

There is only one rib and only one inlet for each of the chambers sothat the water, introduced thereinto, meets with no obstruction orinterference by water entering the same chamber at another point, but isfree to flow smoothly. and regularly through the chamber into thecentral pocket. It will be understood that the provision of more thanone spiral chamber is not merely for the purpose of increasing thecapacity of the water removing means, is in fact not for that purpose atall, but has for its object the prevention of interference in the flowoff of the water, which I have found occurs when there is only onespiral chamber with a plurality of inlets.

It will also be evident that'my invention is not limited to three spiralchambers or to their arrangement as volute spirals in one end of thecylinder. The essence of the invention lies in the provision of aplurality, two or more, of spiral chambers, each having but one inlet,and with one deflector rib for each chamber leading to said inlet, asexpressed in the following claims:

Having thus described my invention, What I claim is:

1. In a steam-heated rotary cylinder, means for removing the water ofcondensation, comprising a plurality of nested independent spiralchambers leading to a com mon outlet, and a deflector rib on thecylinder wall leading into the outer end of each chamber to direct thewater thereinto.

2. In a steam-heated rotary cylinder, 1

3. In a steam-heated rotary cylinder,

, means for removing the water of condensation, comprising three spiralchambers lying in the same transverse plane and terminating at 120apart, a common drain pipe lyin in the axis of the cylinder, and threehelical deflecting ribs on the wall of the cylinder,

{Each of said ribs leading to one of said cham- )ers.

4. In a steam-heated rotary cylinder, means for removing the water ofcondensation, comprising a plurality of chambers for leading the Waterfrom the periphery to the center of the cylinder, each chamber having anopenin adjacent the periphery and an opening adjacent the axis of thecylinder, a common chamber into which said last mentioned openingsdischarge, and means carried by the inner periphery of the cylinder toguide the water into said first mentioned openings.

In testimony whereof I have hereunto set my hand. 7

ALFRED MAOKAY.

